Ship rocks — vessel going round river (10)
I believe the answer is:
icebreaker
'ship' is the definition.
(icebreaker is a kind of ship)
'rocks vessel going round river' is the wordplay.
I cannot quite see how this works, but
'rocks' could be 'ice' (I've seen this before) and 'ice' is located in the answer.
'river' could be 'ea' (I've seen this in other clues) and 'ea' is found in the answer.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for icebreaker that I've seen before include "useful at parties" , "Something to relax social tension" , "Conversation starter" , "Something helping to start a conversation" , "useful at beginning of party?" .)